Write! It's an important skill used in all sorts of ways: jobs, fun, maintaining important relationships, etc.  It's also good for trying out those new words you're learning through your reading.  Over the summer, I plan on writing a lot of letters to friends and family, and keeping a semi-regular journal.  Below are some ideas of things to write over the summer.  I encourage you to keep your writing skills fresh!

Try writing:

A regular journal over the summer, as little as 5 minutes a day (or more, if you want).  Write about your day - what happened, your thoughts and feelings and the people in your day, etc.  Or you can get a family member to ask a question, and then answer it in your journal.

An email or a letter to a family member far away.  Write a letter to a teacher.  Bonus points for sending an actual letter through the actual mail.

A letter to one of your address's elected officials about an issue you feel strongly about.  Keep it informed and respectful.  Here's a website to find your local legislator: https://app.leg.wa.gov/districtfinder/.

A movie review or a book review.  Less summary, more what you think and whether you'd recommend it.

A poster/public awareness/announcement/etc about something you want to share.  Put up a sign on the wall of your house about how your little brother needs to do a better job of keeping the bathroom clean.

Other ideas as posted.  Let me know if you think of something.